Container closure

ABSTRACT

A collapsible container having a body with foldable side walls and a closure with foldable side walls. The body and closure have cooperating tab and abutment means respectively to lock the closure to the body. The abutment means on the closure are biased to a locking position by being located adjacent fold line on the closure side walls.

United States Patent Engel [15] 3,658,237 51 Apr. 25, 1972 [54]CONTAINER CLOSURE [72] Inventor: Karl Engel, Pierrefonds, QuebecsCanada[73] Assignee: Rolph-Clark-Stone Limited, Don Mills,

Ontario, Canada [22] Filed: June24,l970

[21] Appl.No.: 49,299

[52] US. Cl ..229/41 [51] Int. Cl ..B65d 5/36 [58] Field of Search.229/41 R, 41 A, 41 B [56] References Cited UNITED STATES PATENTS2,650,751 9/1953 Goers ..229/4l B Pfafi' ..229/4l B Collura ..229/4l BPrimary Examiner-Richard E. Aegerter Assistant Examinerl. KennethSilverman Attorney-Alan Swabey [5 7] ABSTRACT A collapsible containerhaving a body with foldable side walls and a closure with foldable sidewalls. The body and closure have cooperating tab and abutment meansrespectively to lock the closure to the body. The abutment means on theclosure are biased to a locking position by being located adjacent foldline on the closure side walls.

4 Claims, 6 Drawing Figures PATENTEDAPRZSIHYE 3,658,237

SHEET IUF 2 INVENTOR Karl ENGEL PATH-STE!) APR 2 5 1972 SHEET 20F 2INVENTOR Karl ENGEL A TTORNEY BACKGROUND OF THE INVENTION 1. Field ofthe Invention This invention relates to a container having an improvedclosure.

More particularly, the invention relates to a collapsible, paperboardcontainer having improved locking means for locking the closure of thecontainer when the closure is moved to a closed position.

2. Description of the Prior Art Locking means for the closures ofpaperboard containers are known. However, the known locking meansare'not very effective in maintaining the closures locked at all times.Typical known locking means in a container having a closure panelusually comprise cooperating a tab and an abutment on overlyingcontainer and closure walls when the closure is moved to a position toclose the container. When a container is closed, the abutment on onewall, of either the container or closure, is meant to cooperate with thetab on the wall of the other of the container or closure so as to lockthe closure when in a closed position. Usually, the tab resilientlyrides over the abutment, and once past it, snaps outwardly under theabutment into place. The abutment thus prevents the tab from moving inthe reverse direction. Usually, however, the abutment formed in thecontainer is quite narrow, and because the containers, when made frompaperboard, are not too rigid, the tab an be inadvertently moved pastthe abutment when the closed container is being handled, thus permittingthe closure to become unlocked and leading to the inadvertent opening ofthe container.

SUMMARY OF THE INVENTION The present invention relates to an improvedlocking means for a container having a closure, particularly acollapsible, paperboard container which is more positive acting thanknown locking means. The positive locking action of the locking means isobtained by providing an abutment on one wall which can be biased awayfrom the one wall towardthe other wall carrying the tab when thecollapsed container: is set up, thus ensuring more positive locking ofthe tab by the abutment.

The invention is more specifically directed toward a collapsible,paperboard container having bottom and side walls. The container has aclosure which includes a main body panel and side panels. First meansare provided in the container to permit the side walls to be folded tolie substantially adjacent the bottom wall. Second means are provided inthe closure to permit the side panels of the closure to be folded to liesubstantially adjacent the main body panel. Cooperating first and secondlocking means are provided on the side walls and the side panelsrespectively. The first locking means comprises at least one tabextendable outwardly from one of the side walls of the container when itis in the set-up condition. The second locking means comprises at leastone abutment means carried on one side panel of the closure overlying atleast a portion of the second means when the closure is in the set-upcondition. The cab and the abutment cooperate when the closure andcontainer are in a set-up condition and the closure is in a closedposition on the container to lock the closure.

Preferably, the second means comprise two fold lines in said one sidepanel of the container, said fold lines dividing the one side panel intotwo triangular corner sections and an elongated, trapezoidal, mainsection. The abutment means comprises at least one flap lying adjacentthe said one panel, one portion of said flap adhered to one of saidtriangular sections and the remaining portion freely extending over anadjacent portion of the main section. The remaining portion of the flaphas an upper free edge forming an abutment edge which extendssubstantially parallel to the main panel of the closure but which isspaced downwardly a slight distance therefrom.

The tab is preferably formed adjacent the upper edge of the one sidewall of the container and comprises an extension of a narrow safety flaphingedly connected to a free edge of said one side wall.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described indetail having reference to the accompanying drawings, wherein:

FIG. 1 is a schematic view of the container incorporating the improvedlocking closure;

FIG. 2 is a schematic view of the container of FIG. 1 in the collapsedor folded position;

FIG. 3 -is a plan view of a blank used to form the container shown inFIG. 1;

FIG. 4 is a detail schematic view illustrating one corner of thecontainer showing the formation of the abutment means;

FIG. 5 is a schematic view of the same corner taken from the outsideshowing the formation of the abutment means; and

FIG. 6 is a cross-sectional view showing how the abutment means and thetab on the container and closure cooperate to hold the closure in alocked position.

DESCRIPTION OF THE PREFERRED EMBODIMENT The collapsible container, shownin the set-up condition in FIG. 1, comprises a bottom 3, front and backwalls 5 and 7, and end walls 9 and 11. A narrow safety flap 13 extendsfrom the top free edge of the front wall 5 hingedly connected thereto bya fold line 15.

A closure 17 is provided for the container. It can be a completelyseparate piece, but preferably is attached along one edge to the topfree edge of the back wall 7 of the container along a fold line 29. Theclosure 17 includes a main panel 19, a front closure panel 21, and sideclosure panels 23, 25.

When the container shown in FIG. 1 is to be closed, the safety flap 13is folded along fold line 15 to extend toward the back wall 7 and thetop closure 17 is folded along fold line 29 to close the container. Inthe closed condition, the top and side closure panels 21, 23, 25, lieadjacent the outer surfaces of the frontand end walls 5, 9, and 11,respectively, with the top panel being adjacent the safety flap 13.

The container described above can be made from a single blank ofpaperboard or similar container material with fold lines delimiting thewalls, flaps and panels from one another. The container, shown in FIG.1, can be constructed from a single blank of material as shown in FIG. 3by providing relatively short flaps 33, 35 extending from the end edgesof the front wall 5 and relatively short flaps 37, 39, extending fromthe end edges of the back wall 7. Fold lines 41, 43, 45 and 47 delimitthe front and back and end walls 5, 7, 9 and 11, respectively, from thebottom wall 3. Fold lines 49, 51, 53 and 55 delimit the flaps 33, 35, 37and 39, respectively, from the front and back walls. The end walls 9 and11 are folded up about fold lines 45 and 47 relative to the bottom wall3, as are the front and back walls 5 and 7 about fold lines 41, 43.Flaps 33, 37 are then folded about their respective fold lines andjoined, by suitable adhesive for example, to end wall 9 to join one endof each of the front and back wall s to the end wall 9. Flaps 35, 39 aresimilarly adhered to end wall 11 to form the container shown in FIG. 1.

Flaps 57, 59 extend from the side panels 23, 25, respectively, of theclosure, to be joined to the inner surface of the front panel 21. Theflaps 57, 59 are specifically shaped and adhered to the front panel 21in a manner to be described.

While the container can be constructed from a single blank of materialas described above, it can also, if desired, be constructed from aplurality of panels adhesively adhered together. It is essential,however, that the container be constructed so it can assume a collapsedor folded condition, as shown in FIG. 2. In order to collapse thecontainer, additional fold lines are provided as shown in FIGS. 1 and 3.A fold line 61 is provided in each flap 33, 35, 37 and 39. The fold lineextends up at an angle from the end of each respective fold line 49, 51,53 and 55, adjacent the bottom wall 3, dividing the flaps from the frontand back walls. The fold line 61 preferably extends diagonally at a 45angle to the fold lines 49, 51, 53 and 55.

Two further fold lines 63 are provided in the front closure panel 21which extend down from the upper free corners 65, 67 of the panel 21 atan angle to the fold line 27. The fold lines 63 preferably extend at a45 angle to the fold line 27 dividing the front panel from the mainpanel 19. The fold lines divide the front panel 21 into two triangularcomer sections 81, 83 and a trapezoidal central main section 82.

The fold lines 61, 63 permit the assembled container, shown in FIG. 1,to be collapsed to a flat condition by pushing it on the end walls 9, 11as shown by the arrow A in FIG. 2 and by pushing in on the front closurepanel 21 as shown by the arrow B. End walls 9, 11 are thus folded alongtheir fold lines 45, 47 to lie substantially against bottom wall 3. Thefront wall 5, together with a safety flap 13, is then folded along foldline 41 to lie substantially against bottom wall 3 and overlies endwalls 9, 11. The front closure panel 21 lies substantially against thetop panel 19 of the closure, and side closure panels 23, 25 are alsomoved to overlie the front panel 21 and the top panel through fold line63. The collapsed closure 17, along with back wall 7, is then foldedalong fold line 43 to overlie substantially against the bottom wall 3and the collapsed end and front walls. The container can now be shippedin this collapsed condition from the point of manufacture. When thecontainer is to be used, it is set up from its collapsed or foldedcondition, as shown in FIG. 2, to the position shown in FIG. 1.

The container includes cooperating locking means 71, 73 provided on boththe walls of the container and on the closure 17. The locking means 71comprises at least one, and preferably two, locking tabs 75 extendingfrom at least one of the container walls. Preferably, the locking tabsextend from the front wall 5 of the container in an outward directionfrom the outer face. Each of the tabs 75 are formed by cutting the frontwall 5 along a line 77 which deviates into the front wall from the foldline delimiting the safety flap 13 from the front wall 5. The fold line15 is discontinuous at each out line 77. The cut line for each tab ispreferably located adjacent the end edges of the front wall. When thesafety flap 13 is folded inwardly about the fold line 15 relative to thefront wall 5 prior to packaging the container, the tabs 75 forming partof the flap 13 extend in the opposite direction outwardly from the frontwall to form the locking means 71.

The cooperating second locking means 73 preferably comprise abutmentmeans carried by the side panels of the closure 17. Preferably, theabutment means are carried on the inner surface of the front panel 21 ofthe closure 17. The abutment means are formed by the flaps 57 and 59which join the side panels to the front panel. The flaps 57, 59 areformed to have a top abutment edge 79 spaced slightly below the top edgeof the front panel 21 and below the top panel 19 when adhered to thefront panel. The top edge 79 extends substantially parallel to the toppanel when the container is assembled.

In order to provide positive locking, one portion 85 of each of theflaps 57, 59, is adhered to the inner surface of the triangular endsections 81, 83 of the front panel which are defined by the fold lines63. The other portion 87 of each of the flaps 57, 59 extend past thefold line to lie adjacent, but free from, a portion of the main bodysection 82 of the front panel. The upper, free, abutment edge 79,carried by portion 87 of each flap, is thus unattached to the frontpanel.

The upper free portion 87 of each flap which overlies the main centersection 82 of the front panel 21, and is unattached thereto, is,therefore, free to be biased, by the tendency of the top closure toreturn to its folded position, away from the front panel 21 and towardthe front wall 5 of the container when the container and closure are ina set-up condition and the front panel overlies the front wall when theclosure is in the closed condition. With the abutment edge 79 thusbiased toward the front wall 5, as shown in FIG. 6, a more positivelocking for the tab is obtained. The locking is obtained by moving theclosure 17 to a closed position whereby its front panel 21 asses downover the outside of the front wall 5 to he a acent thereto. During theclosing operation, the flaps 57, 59 ride down over the tabs 75 untiltheir abutment edges 79 pass by the tabs and they are then biased awayfrom panel 21 when the closure is substantially closed. The abutmentedges 79 being biased toward the front wall 5, now positively interferewith the tabs 75 to lock the closure in place and prevent it fromopening.

By providing the abutment edges 79 and locking tabs 75 at the comers ofthe container, where the container construction is more rigid when setup, a more positive locking action is assured.

While the abutments and tabs have been shown to be positioned on thefront wall and panel, they could be equally well positioned on the sidewalls and panels. The fold lines, to permit the container to becollapsed, are then also provided in the side walls and side panels.

I claim:

1. A collapsible paperboard container having a closure, the containerhaving bottom and side walls, a closure for the container, the closureincluding a main body panel and side panels, first means in thecontainer permitting the side walls to be folded to lie substantiallyadjacent the bottom wall, second means in the closure permitting theside panels to be folded to lie substantially adjacent the main bodypanel, cooperating first and second locking means on at least one of theside walls and at least one of the panels respectively, said firstlocking means comprising at least one tab extending from one of saidside walls when the container is in a set-up condition, said secondlocking means comprising at least one abutment means carried on one sidepanel overlying at least a portion of the second means when the closureis in a set-up condition, the tab and abutment means cooperating whensaid closure and container are in a set-up condition and said closurecloses said container, to lock the closure, said container including asafety flap connected to a free edge of aid one side wall, said safetyflap extending inwardly over the bottom wall of the container and saidtab extending outwardly away from the bottom wall with the container ina set-up condition, said tab comprising an extension of the safety flap.

2. A collapsible container as claimed in claim 1, wherein the secondmeans comprise two fold lines in said one side panel, said fold linesdividing the one side panel into two triangular corner sections and anelongated, trapezoidal, main section.

3. A collapsible container as claimed in claim 2, wherein the abutmentmeans comprise at least one flap lying adjacent said one said panel, oneportion of said flap adhered to one of said triangular sections and theremaining portion freely extending over an adjacent portion of said mainsection.

4. A collapsible container as claimed in claim 3, wherein said one flaphas a free upper edge forming an abutment edge which extendssubstantially parallel to the main body panel but is spaced downwardlytherefrom a slight distance.

1. A collapsible paperboard container having a closure, the containerhaving bottom and side walls, a closure for the container, the closureincluding a main body panel and side panels, first means in thecontainer permitting the side walls to be folded to lie substantiallyadjacent the bottom wall, second means in the closure permitting theside panels to be folded to lie substantially adjacent the main bodypanel, cooperating first and second locking means on at least one of theside walls and at least one of the panels respectively, said firstlocking means comprising at least one tab extending from one of saidside walls when the container is in a set-up condition, said secondlocking means comprising at least one abutment means carried on one sidepanel overlying at least a portion of the second means when the closureis in a set-up condition, the tab and abutment means cooperating whensaid closure and container are in a set-up condition and said closurecloses said container, to lock the closure, said container including asafety flap connected to a free edge of aid one side wall, said safetyflap extending inwardly over the bottom wall of the container and saidtab extending outwardly away from the bottom wall with the container ina set-up condition, said tab comprising an extension of the safety flap.2. A collapsible container as claimed in claim 1, wherein the secondmeans comprise two fold lines in said one side panel, said fold linesdividing the one side panel into two triangular corner sections and anelongated, trapezoidal, main section.
 3. A collapsible container asclaimed in claim 2, wherein the abutment means comprise at least oneflap lying adjacent said one said panel, one portion of said flapadhered to one of said triangular sections and the remaining portionfreely extending over an adjacent portion of said Main section.
 4. Acollapsible container as claimed in claim 3, wherein said one flap has afree upper edge forming an abutment edge which extends substantiallyparallel to the main body panel but is spaced downwardly therefrom aslight distance.